Nokea
Which of the following DNA polymerases cleaves a DNA sequence at the direction of 5' → 3'?
- A. DNA polymerase I
- B. DNA polymerase II
- C. DNA polymerase III
- D. DNA polymerase IV
Correct Answer: A
Rationale: The correct answer is A: DNA polymerase I. DNA polymerase I has both 5' to 3' polymerase activity and 5' to 3' exonuclease activity, allowing it to cleave DNA in the 5' to 3' direction. This enzyme can remove RNA primers during DNA replication by cleaving them in the 5' to 3' direction and replace them with DNA nucleotides. DNA polymerase II, III, and IV do not have the same exonuclease activity as DNA polymerase I, so they are not capable of cleaving DNA sequences in the 5' to 3' direction like DNA polymerase I.
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What cytokine is produced by Regulatory T cells to suppress immune responses?
- A. IL-2
- B. IL-10
- C. IFN-gamma
- D. TNF-alpha
Correct Answer: B
Rationale: The correct answer is B: IL-10. Regulatory T cells produce IL-10 to suppress immune responses by inhibiting the activation and function of other immune cells. IL-2 (A) is mainly produced by activated T cells to promote proliferation. IFN-gamma (C) is produced by T cells and NK cells to enhance immune response. TNF-alpha (D) is produced by macrophages and T cells to induce inflammation. IL-10 stands out as the suppressor cytokine in this context.
What treatment is commonly used for anaphylaxis?
- A. Antihistamines only
- B. Epinephrine
- C. Corticosteroids only
- D. Antibiotics
Correct Answer: B
Rationale: The correct answer is B: Epinephrine. Epinephrine is the first-line treatment for anaphylaxis as it rapidly reverses the symptoms by constricting blood vessels, relaxing airway muscles, and increasing heart rate. It is crucial in preventing severe complications and can be life-saving. Antihistamines (choice A) only target histamine effects, which are not sufficient in managing anaphylaxis. Corticosteroids (choice C) are used as adjunct therapy but are not as immediate or critical as epinephrine. Antibiotics (choice D) are not indicated for anaphylaxis treatment. Therefore, epinephrine is the most appropriate choice for managing anaphylaxis effectively.
The industrial nurse examines an employee who complains of right shoulder pain on abduction. He points with one finger to the exact location of the pain and mentions that he won a racquetball tournament yesterday. The nurse suspects the employee is suffering from which problem?
- A. Rotator cuff tear
- B. Bursitis
- C. Dislocation
- D. Subluxation
Correct Answer: B
Rationale: The correct answer is B: Bursitis. The employee's complaint of shoulder pain on abduction, localized pain with a specific trigger (racquetball tournament), and no mention of trauma or instability suggest an inflammatory condition like bursitis. The other choices are incorrect because a rotator cuff tear typically presents with weakness, dislocation with a history of trauma and visible deformity, and subluxation with recurrent episodes of partial dislocation.
Vertebrate eyes are Single-lens eyes with
- A. Light is focused by the curved cornea and lens
- B. Changing the shape of the lens focuses near and far
- C. Photoreceptor cells in the retina detect light
- D. All above
Correct Answer: D
Rationale: The correct answer is D because vertebrate eyes have single-lens eyes where light is focused by the curved cornea and lens (A), and changing the shape of the lens allows for focusing at different distances (B). Additionally, photoreceptor cells in the retina detect light (C). Therefore, all of the above statements are true, making D the correct choice. Choice A is incorrect because it does not encompass the entire process of vision in vertebrate eyes, missing the role of changing the lens shape. Choice B is incorrect as it only addresses the lens shape without mentioning the role of the cornea in focusing light. Choice C is incorrect as it only focuses on the function of photoreceptor cells in the retina without considering the lens and cornea's role in focusing light.
A client is being administered the first dose of belimumab for a systemic lupus erythematosus flare. What actions by the nurse are most appropriate? (Select one that does not apply.)
- A. Observe the client for at least 2 hours afterward.
- B. Instruct the client about the monthly infusion schedule.
- C. Inform the client not to drive or sign legal papers for 24 hours.
- D. Ensure emergency equipment is working and nearby.
Correct Answer: C
Rationale: The correct answer is C: Inform the client not to drive or sign legal papers for 24 hours. This is because belimumab can cause dizziness and fatigue as side effects, which may impair the client's ability to drive or make important decisions. It is crucial for the nurse to ensure the safety of the client and others by advising against these activities for 24 hours post-administration.
Choice A: Observing the client for at least 2 hours is important for monitoring immediate adverse reactions, but it is not the most appropriate action in this scenario.
Choice B: Instructing the client about the monthly infusion schedule is important for treatment adherence, but it is not the most immediate concern after the first dose administration.
Choice D: Ensuring emergency equipment is working and nearby is important for safety precautions, but advising the client not to drive or sign legal papers is more directly related to the potential side effects of belimumab.